Recently I was the high bidder on a foreclosure at sheriff's auction in MN and I currently hold the sheriff's certificate for the property.  This is my first sheriff's auction and there were property taxes that were unpaid plus a small penalty.  

Questions: Should I pay the property taxes that are currently past due?  Or should I wait until the redemption is up to see if I end up with the property causing the taxes to potentially be delinquent with the county + more penalty?  Would the homeowner be required to pay those taxes back to me if they redeem?

The redemption runs into 2021.  From what I understand in Minnesota, if they go past the current year when they were due (2020), they will be considered delinquent and the county could impose a tax lien on the property where there currently is not one.  In the event that the homeowner redeems, my understanding is that I can charge the original mortgage interest rate + reasonable attorney fees + property taxes I paid for the homeowner + necessary expenses to keep the home from declining?  

Am I correct in assuming that I can charge the property taxes that I would pay on their behalf back to them in the event that they redeem?  If anyone has some experience in this area or specifically with this in MN, I would love some feedback.  My thought is that I should pay them to avoid additional penalties/problems and I am hoping that they would legally be required to repay them to me as part of a redemption total.